Front-loader dishwashing machine with heat recovery

ABSTRACT

A dishwashing machine for commercial use is provided, which has a dishwashing chamber with a front door which can be opened for loading and unloading the dishwashing chamber with items to be cleaned. Furthermore, the dishwashing machine has at least one condensation precipitation device, which is connected to the dishwashing chamber and is equipped with at least one fan for sucking and/or blowing vapor and/or air out of the closed dishwashing chamber. The condensation precipitation device also has at least one condensation surface for condensation of vapor. The dishwashing machine additionally has an inlet-air channel for supplying ambient air into the dishwashing chamber. The inlet-air channel is provided with an inlet-air fan.

This nonprovisional application claims priority to German PatentApplication No. DE 102007007133.9, which was filed in Germany on Feb.13, 2007, and to U.S. Provisional Application No. 60/907,330, which wasfiled on Mar. 28, 2007, and which are both herein incorporated byreference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to a dishwashing machine for commercial use.Dishwashing machines such as these are used, for example, in largekitchens, in order to clean plates and dishes, glasses, flatware, traysor similar articles.

2. Description of the Background Art

In addition to conveyor-belt transportation and basket transportationdishwashing machines, single-chamber systems are also used in largekitchens, in particular in large kitchens for hotels, guest houses,factory canteens, hospitals, the authorities, schools or similarfacilities. Single-chamber systems such as these with a singledishwashing chamber are frequently also referred to as “front-loaders”and have a dishwashing chamber with a front door which can be opened forloading and unloading the dishwashing chamber with items to be cleaned.Dishwashing machines of this type may be designed for various purposesand, for example, may be used as free-standing appliances or else asso-called appliances used below work surfaces.

In contrast to domestic appliances, dishwashing machines for commercialuse are subject to the problem that the throughput times must beconsiderably reduced. While dishwashing programs of up to more than 2hours are normal for domestic appliances, dishwashing cycles from a few10 s of seconds up to a few minutes are normal in the field ofcommercial applications. For this purpose, dishwashing machines forcommercial typically have a plurality of tanks so that a final washingliquid is heated (for example in a final washing tank) separately duringa washing cycle (for which purpose, for example, a washing tank isused), in order then to carry out a final washing cycle immediatelyafter completion of the washing cycle, or with only a short time delay.After final washing (although a further drying cycle may also beprovided), the front door can be opened so that the items that have beencleaned can be removed.

However, one problem with commercial dishwashing machines such as theseis that, when the front door is opened, considerable amounts of vaporin. the form of water vapor can escape into the working environment, forexample a large kitchen, thus considerably increasing the temperatureand the air humidity in this area. This water vapor makes the work ofthe operator considerably harder. For example, operation of machinessuch as these by those wearing spectacles is subject to considerabledifficulties.

In order to overcome this problem, it is normal practice beforeunloading the dishwashing machines to wait until the dishwashing chamberhas cooled down, in order to reduce the vapor load in the workingenvironment. However, in practice, this procedure is not only associatedwith the disadvantage of reduced throughput of plates and dishes to becleaned, but also leads to plates and dishes that have been cleaned anddried being subjected to increased moisture as a result of vaporprecipitating on the surfaces of the plates and dishes as they cooldown.

By way of example, in order to solve this problem, DE 10 2005 023 428 A1discloses a commercial dishwashing machine having a spraying chamber forholding items to be cleaned, which has a fan in order to produce an airflow. This air flow is passed from an air inlet underneath the area forthe items to be cleaned, for example a gap underneath a folded door ofthe dishwashing machine, through the spraying chamber to an air outlet,with a deflector device being used. The air flow is then passed to anoutlet by the fan.

However, the solution proposed in DE 10 2005 023 428 A1 has theparticular disadvantage that the air supply is uncontrolled and isessentially associated with a leak in the form of a gap underneath thefront door. However, water vapor, or even liquid, can easily escapethrough this gap into the working environment during operation of thedishwashing machine. Furthermore, this gap can easily become dirty thusgreatly reducing the functionality of the suction process.

In addition, further solutions have been proposed to solve the problemof water vapor formation, in particular once again in the field of smallappliances for domestic use. For example, WO 2006/12062 A1 and WO2006/123947 A1 each disclose small appliances which are provided withvapor suction. However, these appliances have the disadvantage that, inthese appliances, the vapor is emitted directly into the workingenvironment.

SUMMARY OF THE INVENTION

It is therefore an object of the present invention to provide adishwashing machine for commercial use which avoids the disadvantages ofthe dishwashing machines known from the prior art and, in particular,offers a reliable, low-maintenance solution to the problem ofwater-vapor formation in the working environment.

As described above, the proposed dishwashing machine is designed forcommercial use. It is designed to clean many types of item to becleaned, in particular plates and dishes, flatware, trays, boxes,glasses and/or similar items to be cleaned that are used in largekitchens. However, other types of items to be cleaned may, of course,also be used, for example items to be cleaned from the field of nursingand hospitals.

The dishwashing machine has a dishwashing chamber with a front doorwhich can be opened for loading and unloading the dishwashing chamberwith items to be cleaned. This front door will normally have a hinge inorder, for example, to allow the front door to be tilted downwards,upwards or to the side, in order in this way to provide access to thedishwashing chamber. Other types of front doors are, however, alsofeasible. For example, it is possible to provide a combination of asliding door and folding door. In this case, by way of example, when thelower half of the door is folded down, the upper half can be pushedupwards by means of a linkage.

Furthermore, the dishwashing machine has at least one condensationprecipitation device, which is connected to the dishwashing chamber andhas at least one fan for sucking or blowing vapor and/or air out of theclosed dishwashing chamber. This condensation precipitation device hasat least one condensation surface for the condensation of vapor.

In contrast to the prior art, however, the dishwashing machine also hasan inlet-air channel for supplying ambient air into the dishwashingchamber. This inlet-air channel is provided with an inlet-air fan.

The refinement according to the invention of the dishwashing machineavoids the disadvantages of the prior art as described above in thatambient air can be introduced into the dishwashing chamber, for exampleby means of the inlet-air fan, thus ensuring pressure equalizationwithin the dishwashing chamber. The inlet-air channel may, inparticular, be designed so as to virtually completely preclude thisinlet-air channel from becoming dirty during practical use. Theemergence of liquid can also be avoided by appropriate design of thisinlet-air channel. By way of example, damage to sensitive items to becleaned can be avoided by avoiding the problem of a vacuum pressurebeing formed within the dishwashing chamber.

By way of example, the condensation precipitation device may beaccommodated entirely or partially in a top part of the dishwashingchamber, and/or this condensation precipitation device may beaccommodated (once again entirely or partially) in a rear wall of thedishwashing chamber.

In order to avoid the pressure equalization problem described above andin order to improve the reliability of the supply of ambient air, thedishwashing machine may, for example, be designed such that the fan andthe inlet-air fan are operated synchronized in time. For example, anappropriate controller can be provided for this purpose, synchronizingthese fans in time. In particular, this synchronization can be carriedout in such a manner that the fan and the inlet-air fan are started atthe same time and/or with a predetermined time offset. After the suctionprocess, the inlet-air fan can then be stopped, for example, at the sametime as or at a time before the fan. This allows the remaining vapor tobe sucked out of the dishwashing chamber.

The at least one inlet-air channel can be in the form of an elongatedchannel, although it may also be in the form of a connecting stub orshort piece of channel. This inlet-air channel can be at least partiallyarranged in the area of the rear wall of the dishwashing chamber. Theinlet-air channel may have an inlet air opening to the workingenvironment on the rear face and/or the top face of the dishwashingchamber. Furthermore, the inlet-air channel may comprise a blowing-inopening in the bottom area of the dishwashing chamber. The combinationof these refinements is particularly advantageous since, in this case,an air flow and/or a vapor flow can be produced within the dishwashingchamber, flowing upwards from the bottom area of the dishwashingchamber. In this case, the expression “in the bottom area” should notnecessarily be understood as meaning an arrangement in the bottom of thedishwashing chamber itself, but an arrangement in the side walls of thedishwashing chamber is preferable, which is adjacent to the bottom ofthe dishwashing chamber and/or which is no more than ⅓ to ½ of theoverall height of the dishwashing chamber away from the bottom.

In order to prevent water vapor from flowing out through the inlet-airchannel, the inlet-air channel may, for example, be equipped with aninlet air valve. This inlet air valve is intended to be designed toswitch quickly and to allow large amounts of inlet air to pass throughit so that, by way of example, inlet air flaps (for examplespring-loaded control flaps) can advantageously be used.

In order to provide further routing for the flow within the dishwashingchamber and to ensure more uniform drying of the items that have beencleaned, flow guiding devices can be provided, in particular in the areaof the top of the dishwashing chamber. These flow guiding devices may inparticular have flow laminates and/or perforated intermediate covers.

In order to further assist the drying process and to allow pressureequalization as well, the condensation precipitation device mayadditionally be designed such that at least a portion of the flow of theair which is sucked out of the dishwashing chamber is passed back againinto the dishwashing chamber after flowing through the condensationprecipitation device (and therefore after at least partial drying).

In particular, the condensation precipitation device may have at leastone chamber with at least one inlet and at least one outlet, as well asat least one condensation outflow for emission of condensation. By wayof example, this condensation outflow can be passed back again into thedishwashing chamber, into one or more tanks of the dishwashing machine,or the condensation outflow can be connected to an outflow and/oroutlet. The fan of the condensation precipitation device may beconnected to the inlet and/or to the outlet of the condensationprecipitation device, or it may also be provided in the intermediatearea, for example at a point within a flow channel of the condensationprecipitation device.

In particular, the condensation precipitation device may have at leastone cold plate, at least one cold plate which is sprayed with a coolingmedium, at least one heat exchanger through which a cooling medium flows(for example a plate-type heat exchanger and/or a serpentine coolingcoil-type heat exchanger), or any desired combination of these condenserelements. The at least one condenser element is preferably aligned at anangle to the horizontal. Furthermore, the at least one condenser elementmay have a laminate arrangement, for example an arrangement of aplurality of cooling surfaces which are arranged essentially parallel.Alternatively or additionally, a meandering arrangement can also beprovided, for example by inserting a plurality of cooling surfaces intoone another with an offset with respect to one another. This in turnmakes it possible to define a flow channel which likewise has ameandering profile. Any desired parallel arrangement of at least twocondenser elements is also feasible.

The condensation precipitation device may, for example, have one or morepassive condenser elements in the form of cooling surfaces.Alternatively or additionally, the condensation precipitation devicemay, however, also have at least one condenser element which can becooled with water, in which case at least one first condenser connectionof the condenser element can be connected to a water supply, inparticular to a fresh-water supply. In this case, it is particularlyadvantageous for at least one second condenser connection of thecondenser element to be connected to a tank for the dishwashing machine,in particular to a final washing tank. This allows at least a portion ofthe condensation heat which has been emitted from the vapor to thecooling water to be fed back and reused, in order for example toappropriately heat the final washing liquid.

In particular, the dishwashing machine can be designed in order to carryout a dishwashing program. For example, as mentioned above, thedishwashing machine may for this purpose have one or more controllers,for example an electronic controller, in particular a controller whichhas one or more computers (for example microcomputers). In particular,this computer can be appropriately programmed to carry out thedishwashing program.

In this case, the condensation precipitation device is intended to beoperated in at least one program step in the dishwashing program inorder to suck vapor and/or air out of the dishwashing chamber (suctionstep). For example, this suction program step can be carried out at theend of the dishwashing program. By way of example, as described above,the fan and the inlet-air fan can be operated synchronized in time inorder to carry out this suction program step.

In this case, it is particularly advantageous for items to be cleanedwhich are accommodated in the dishwashing chamber to be finally washedin at least one final washing program step using a final washing liquidfrom a final washing tank. Cooling water from the condensationprecipitation device can then be heated in a. subsequent suction programstep by vapor and/or air from the dishwashing chamber, with the heateddishwashing water being passed into the final washing tank. This resultsin heat being partially recovered, and the time required for subsequentheating of the final dishwashing water can be shortened. This savesenergy, and the dishwashing cycle of the dishwashing machine can beshortened further.

In particular, the final washing tank may have a two level controlsystem, for example with the final washing program step being carriedout until the level in the final washing tank has reached a lower level.The level in the final washing tank can then be raised again in thesubsequent suction program step, until the upper level is reached again.Other program configurations are, however, also feasible.

A liquid valve for controlling a supply of the cooling medium can alsobe provided when using a liquid-cooled condenser element, in particulara water-cooled condenser element. The dishwashing machine isadvantageously designed such that the timings of the operation of thisliquid valve and the operation of the fan (and if appropriate theoperation of the inlet-air fan as well) are synchronized. In particular,the liquid valve can also be opened and the fan can be startedessentially at the same time. The stopping of these two elements canalso be synchronized in time, although it is preferable to stop the fanwith a certain lag.

Further scope of applicability of the present invention will becomeapparent from the detailed description given hereinafter. However, itshould be understood that the detailed description and specificexamples, while indicating preferred embodiments of the invention, aregiven by way of illustration only, since various changes andmodifications within the spirit and scope of the invention will becomeapparent to those skilled in the art from this detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will become more fully understood from thedetailed description given hereinbelow and the accompanying drawingswhich are given by way of illustration only, and thus, are not limitiveof the present invention, and wherein:

FIG. 1 shows a front view of an embodiment of a dishwashing machineaccording to the invention;

FIG. 2 shows a section illustration in the form of a side view of theembodiment of the dishwashing machine shown in FIG. 1;

FIGS. 3A to 3D show various embodiments of condensation precipitationdevices;

FIGS. 4A and 4B show two embodiments of a condenser element with liquidcooling;

FIG. 5 shows an embodiment of a condensation precipitation device withpartial feedback of the dried air to the dishwashing chamber; and

FIG. 6 shows an embodiment of a liquid system for one preferreddishwashing machine, illustrated schematically.

DETAILED DESCRIPTION

FIGS. 1 and 2 show an embodiment of a dishwashing machine 110 accordingto the invention, illustrated schematically. The dishwashing machine 110is in the form of a front-loader and has a dishwashing chamber 112 witha housing 114. On its front, the housing 114 has a front door 116, whichcan be folded downward in this embodiment, in order to allow items to becleaned to be loaded in the dishwashing chamber 112. This loadingprocess can be carried out either directly, by placing items to becleaned in appropriate holders within the dishwashing chamber 112, orthis can be done by the use of baskets for the items to be cleaned.Items to be cleaned and the corresponding devices are not illustrated inFIGS. 1 and 2.

As can be seen in particular from the section illustration in the formof a side view shown in FIG. 2, the dishwashing machine 110 has a coverpart 118 which is in the form of a condensation precipitation device120. Furthermore, this exemplary embodiment of the dishwashing machinehas an inlet-air channel 122 in its rear wall (that is to say the sideopposite the front door 116). This inlet-air channel has an inlet airopening 124 on the upper face of the dishwashing machine 110. Aninlet-air fan 126 is accommodated in the inlet-air channel 122 in thearea of this inlet air opening 124. The inlet-air channel 122 opens intothe dishwashing chamber 112 at a blowing-in opening 128. This blowing-inopening 128 is in this case arranged in the lower area of thedishwashing chamber 112, that is to say immediately above a liquid levelin a washing tank 130 which is accommodated underneath the dishwashingchamber 112. In this embodiment, a spring-loaded inlet air flap 132 isalso arranged within the inlet-air channel 122, can be used as a flowvalve and makes it more difficult, for example, for water vapor toemerge from the dishwashing chamber 112 into the working environment.

The condensation precipitation device 120 has a chamber 134 with aninlet 136 and an outlet 138. In this case, the outlet is arranged on theupper face of the dishwashing machine 110, although, alternatively oradditionally, as is indicated by way of example in FIG. 1, the outlet138 could also be arranged at the side of the dishwashing machine 110.

In the embodiment illustrated in FIG. 2, a condenser element 140 isarranged within the chamber 134 and, in this simple exemplaryembodiment, is a simple cold plate 142 with condensation surfaces 144.The cold plate 142 defines a flow channel 146 within the condensationprecipitation device 120. A fan 148 is arranged in the outlet 138, andis preferably operated in synchronism with the inlet-air fan 126, asdescribed above.

Furthermore, the condensation precipitation device 120 has acondensation outflow 150. In this embodiment, condensation can flowdirectly out of the condensation precipitation device 120 into thewashing tank 130 via this condensation outflow 150. Alternatively, anoutlet could also be provided into an outflow or, as will be describedin more detail further below, condensation could be transferred to afinal washing tank.

A flow guiding device 152, for example in the form of a perforated coverplate, is provided substantially immediately underneath the condensationprecipitation device 120, in the trough area of the dishwashing chamber112. This perforated cover plate is used to homogenize air flows withinthe chamber 112, in order in this way to dry the items that have beencleaned, more uniformly.

The fan 148 of the condensation precipitation device 120 and theinlet-air fan 126 are preferably operated in synchronism, as describedabove. This allows vapor and/or moist air to be sucked out of thedishwashing chamber 112 into the chamber 134 of the condensationprecipitation device 120 without any need for pressure equalization, asa result of leaks in the housing 114 of the dishwashing chamber 112 (forexample a gap underneath the front door 116). The condensationprecipitation device ensures that moisture is reliably extracted fromthe air from the dishwashing chamber 112, before it can escape into theworking environment.

FIGS. 3A to 3D show various alternative exemplary embodiments of thecondensation precipitation device 120 which can be used as alternativesto the exemplary embodiment shown in FIG. 2. It should be noted that, inaddition to the condensation precipitation device 120 being formed inthe cover part, an analogous configuration on the rear face of thedishwashing chamber 112 (that is to say oriented vertically) is alsofeasible.

The arrangement in FIG. 3A shows a meandering arrangement of passivecold plates 142, that is to say in this example cold plates 142 whichare not liquid-cooled, with condensation surfaces 144. These arearranged at an angle (that is to say at an angle to the horizontal) andthus allow the condensation to flow away to the condensation outflow150. In addition, a connecting stub of the inlet 136 can additionally beequipped with a rim 154 which extends into, the chamber 134 in order toprevent the condensation from flowing away into the inlet 136.Otherwise, the exemplary embodiment of the condensation precipitationdevice 120 corresponds essentially to that of the condensationprecipitation device 120 in the exemplary embodiment shown in FIG. 2. Anoutlet air flow 156 flows through the flow channel 146 of the chamber134 in a meandering form, flowing a number of times over thecondensation surfaces 144 of the condenser plates 142. Furthermore, inthe exemplary embodiment shown in FIG. 3A, an outflow 158 is providedinto which the condensation can run away. As described above, thisrefinement is also optional.

FIG. 3B shows one exemplary embodiment of a condensation precipitationdevice 120, whose function and design correspond essentially to those ofthe example shown in FIG. 3A, but in which the cold plates 142 aresprayed via spraying elements 160 with cooling liquid, for example withcold water. This cooling liquid runs, together with the condensation,away into the condensation outflow 150 and can be supplied either to awaste water connection or, alternatively or additionally, to one or moretanks for the dishwashing machine 110, as well. Spraying the cold plates142 with cooling liquid therefore represents an intermediate stepbetween a passive configuration of the condenser elements 140 and anactive configuration, and increases the efficiency of the precipitationof the condensation in the outlet air flow 156 from which moisture is tobe removed.

FIG. 3C shows a further exemplary embodiment, likewise showing amodified form of the condensation precipitation device 120 asillustrated in FIG. 3A. Once again, cold plates 142 are used as thecondenser elements 140 and are incorporated in the chamber 134 at anangle to the horizontal (for example at an angle of about 2 to 10°,preferably about 5°, as is also the case in the other exemplaryembodiments). In contrast to the exemplary embodiment in FIGS. 3A and3B, this exemplary embodiment does not have a meandering arrangement,and, instead, the cold plates 142 are in the form of perforated coldplates, each having one or more openings 162 through which the air 156from which moisture is to be removed can flow from the inlet 136 to theoutlet 138. The refinements shown in FIGS. 3A and 3C can, of course,also be combined so that, for example, openings 162 can also be providedin the cold plates 142 in the meandering arrangement shown in FIGS. 3Aand 3B.

In contrast to the passive or semi-passive embodiments shown in FIGS. 3Ato 3C, active cooling is provided in FIG. 3D. In this case, thecondensation precipitation device 120 once again, as in FIGS. 3A to 3Cas well, initially has a chamber 134, for example at an angle to thehorizontal, with an inlet 136 and an outlet 138, a condensation outflow150 and a condenser element 140. However, in this case, no passivecooling is provided for the condenser element 140, with cooling beingprovided via serpentine cooling coils 164, instead. In this case, thereare various possible ways to design the condenser element 140, andexamples of these are illustrated in FIGS. 4A and 4B.

For example, in the embodiment shown in FIG. 4A, the condenser element140 is in the form of a pure serpentine cooling coil 164, having a firstcondenser connection 166 for supplying cooling liquid, and a secondcondenser connection 168 as the outflow for the cooling liquid. Theserpentine cooling coil 164 therefore forms a heat exchanger 170 inwhich an amount of heat is transferred from the air 156 from whichmoisture is to be removed to the cooling liquid of the heat exchanger170.

In contrast, in the embodiment shown in FIG. 4B, the heat exchanger 170of the condenser element 140 is in the form of a plate-type heatexchanger 172, with flat condensation surfaces 144. Once again,serpentine cooling coils 164 can be provided in the interior of theplate-type heat exchanger 172 and are once again passed, for example ina meandering shape, through the heat exchanger 170, or a cooling mediumcan flow completely and homogeneously through the plates.

Other types of heat exchangers are also possible as alternatives to theembodiments of the condenser elements 140 illustrated in FIGS. 3D and4A, 4B. Combinations of the illustrated heat exchangers 170 with othertypes of condenser elements 140, for example with passive cold plates142, are also feasible.

In the embodiment of the condensation precipitation device 120 which isillustrated in FIGS. 2 and 3A to 3D, the fan 148 is in each casearranged in the area of the outlet 138. However, this fan 148 can alsobe designed in an alternative form, for example with the chamber 134 ofthe condensation precipitation device 120 not being connected directly,but via one or more tubes. In this case, the fan 148 should be designedand configured to ensure that the flow of outlet air 156 through thecondensation precipitation device 120 from the dishwashing chamber 112is as great as possible, with the amount of air in each case beingmatched to the capability for separation of condensation on thecondenser elements 140.

In this case, however, the fan 148 can also be connected to the inlet136 of the condensation precipitation device 120. Alternatively oradditionally, this fan 148 can also be arranged in the flow channel 146(for example in the meandering configuration shown in FIG. 3A) betweenthe cold plates 142. In order to increase the suction performance, aplurality of fans 148 can also be provided, although this increases thedesign complexity and the operating costs. In order to overcome thisdisadvantage, FIG. 5 shows one exemplary embodiment of the condensationprecipitation device 120 which not only sucks air out of the dishwashingchamber 112, but passes it over condenser elements 140. In this case, inthe illustrated exemplary embodiment, these condenser elements 140 areonce again in the form of cold plates 142 although, in this exemplaryembodiment, they are arranged vertically rather than horizontally. Thiswould be worthwhile, for example, for an arrangement of the condensationprecipitation device 120 on the rear face of the dishwashing machine110. In an analogous manner, the condensation precipitation device 120as shown in FIG. 5 may, however, also be designed as a horizontalcondensation precipitation device. Alternatively or additionally, inaddition to the use of cold plates 142, other refinements are alsofeasible, for example once again the refinements with heat exchangers170 as described above.

However, the flow channel 146 splits immediately adjacent to the fan 148that is incorporated in. the flow channel 146 (with the motor 174 forthe fan 148 in this case being arranged outside the chamber 134). Whilea portion of the air 156 is allowed to escape via the outlet 138 intothe working environment, a portion of the flow is once again fed backinto the dishwashing chamber 112 via a return line 176, where it assiststhe pressure equalization ˜process, in order then to be passed backagain via the input suction to the inlet 136 of the condensationprecipitation device 120. This results in at least a portion of the flowof air 156 passing over the condenser elements 140 repeatedly. Inaddition to assisting the pressure equalization process, this refinementtherefore results in a further reduction in the water vapor escapinginto the working environment. The ratio between the flow element that isfed back and the flow element that is ejected may, for example begoverned by the opening cross sections of the outlet 138 and the returnline 176 and may be adjusted, for example by means of one or more slidesand/or valves, in order to achieve optimum drying.

FIG. 6 schematically illustrates one preferred refinement of thedishwashing system in the dishwashing machine 110, including thecondensation precipitation device 120. In this case, in this exemplaryembodiment, a heat exchanger 170 is provided in the condensationprecipitation device 120, and is represented symbolically here in theform of a serpentine cooling coil 164. Air 156 is passed via the heatexchanger 170 through the inlet 136 by means of the fan 148 from thedishwashing chamber 112 (indicated only symbolically here), in orderfinally to be ejected into the surrounding area via the outlet 138. Theinlet-air channel 122, in which the inlet-air fan 126 is arranged, opensinto the dishwashing chamber 112 at a blowing-in opening 128.Essentially, reference should be made to the exemplary embodiment shownin FIG. 2 with regard to the possible configuration of the dishwashingchamber 112. The figure does not show a washing tank 130 which, forexample, is arranged in the bottom area of the dishwashing chamber 112,or is in the form of a separate tank.

By way of example the heat exchanger 170 can be designed according toone of the embodiments shown in FIGS. 4A and 43. Alternatively however,it is also feasible to use the condensation precipitation device 120 inthe “semi-active” embodiment shown in FIG. 33. In this case, a firstcondenser connection 166 of the heat exchanger 170 is connected to acold water connection 178. The second condenser connection 168 is incontrast preferably connected via a free outflow 180 (for example via afree-running section) to a final washing tank 182 for the dishwashingmachine 110. The inlet flow of fresh water. via the cold waterconnection 178 into the heat exchanger 170 can be controlled via aliquid valve 184, for example a solenoid valve.

The final washing tank 182 in this exemplary embodiment is preferably inthe form of a two-level tank, having an upper level sensor 186 and alower level sensor 188. The final washing tank 182 is connected via apump 190 and a pipeline system 192 to a spraying system 194, in order toapply liquid to the items to be cleaned.

Furthermore, the dishwashing machine 110 may have a controller 196which, for example, can be designed as described above, that is to sayin particular may comprise one or more computers, and which ispreferably programmed to carry out a dishwashing program. By way ofexample (not illustrated in FIG. 6), the controller 196 can checkinformation from the level sensors 186, 188, can operate the pump 190and can operate the liquid valve 184 and the fan 148 and/or 126.

Thus, as already described above, it is possible to carry out a finalwashing program step first of all, in which (for example following oneor more washing steps in which the dishwashing machine 110 is operatedin the circulation mode), the plates and dishes in the dishwashingchamber 112 are finally washed using final washing liquid from the finalwashing tank 182. For example, in this case, the level of the finalwashing liquid in the final washing tank 182 can fall from the level ofthe upper level sensor 186 to the level of the lower level sensor 188.When this lower level is reached, the controller 196 preferablyautomatically stops the pump 190. The liquid valve 184 is preferablyclosed during this final washing program step.

The fan 148 can then be started in a suction program step, as well asthe inlet-air fan 126 (at the same time or preferably with just a slighttime offset). Furthermore, the liquid valve 184 can be opened (likewiseat the same time or preferably with a slight time offset). During thisprocess, cooling water flows through the heat exchanger 170, andcondensation can be precipitated on the heat exchanger 170. At leastsome of the air 156 which has been sucked out of the dishwashing chamber112 has the moisture removed from it before it is allowed to escape tothe surrounding area again.

“Consumed” cooling water, which has absorbed heat from the vapor fromthe dishwashing chamber 112 after flowing through the heat exchanger170, is supplied via the free outflow 180 to the final washing tank 182until the upper level, as defined by the upper level sensor 186, isreached again. The liquid valve 184 is then closed. The fan 148 (and ifappropriate the inlet air fan 126) can be switched off, and the suctionprogram step ended, at the same time as the liquid valve 184 is closed,or a certain lag can preferably be made use of, within which air 156 isstill sucked out of the dishwashing chamber 112.

The invention being thus described, it will be obvious that the same maybe varied in many ways. Such variations are not to be regarded as adeparture from the spirit and scope of the invention, and all suchmodifications as would be obvious to one skilled in the art are to beincluded within the scope of the following claims.

1. A dishwashing machine comprising: a dishwashing chamber with a frontdoor that is configured to be opened for loading and unloading thedishwashing chamber with items to be cleaned; at least one condensationprecipitation device connected to the dishwashing chamber, thecondensation precipitation device having at least one fan for suckingand/or blowing vapor and/or air out of the closed dishwashing chamber,the condensation precipitation device having at least one condensationsurface for condensation of vapor; and an inlet-air channel forsupplying ambient air into the dishwashing chamber, the inlet-airchannel being provided with an inlet-air fan.
 2. The dishwashing machineaccording to claim 1, wherein the condensation precipitation device isaccommodated entirely or partially in a top part of the dishwashingchamber.
 3. The dishwashing machine according to claim 1, wherein thecondensation precipitation device is accommodated entirely or partiallyin a rear wall of the dishwashing chamber.
 4. The dishwashing machineaccording to claim 1, wherein the dishwashing machine operates a secondfan and the inlet-air fan such that they are synchronized in time tostart them at a same time and/or with a predetermined time offset. 5.The dishwashing machine according to claim 4, wherein the dishwashingmachine stops the inlet-air fan at the same time as or at a time beforethe second fan.
 6. The dishwashing machine according to claim 1, whereinthe inlet-air channel is arranged at least partially in an area of therear wall of the dishwashing chamber.
 7. The dishwashing machineaccording to claim 1, wherein the inlet-air channel has an inlet airopening to a working environment on the rear face and/or a top face ofthe dishwashing chamber.
 8. The dishwashing machine according to claim1, wherein the inlet-air channel comprises a blowing-in opening providedin a bottom area of the dishwashing chamber.
 9. The dishwashing machineaccording to claim 1, wherein the inlet-air channel has an inlet airvalve and/or an inlet air flap.
 10. The dishwashing machine according toclaim 1, wherein at least one flow guiding device is provided in a coverarea of the dishwashing chamber and is designed to assist flow to passuniformly through the dishwashing chamber, and wherein the flow guidingdevice comprises flow laminates and/or a perforated intermediate cover.11. The dishwashing machine according to claim 1, wherein thecondensation precipitation device is designed such that at least aportion of the flow of the air which is sucked out of the dishwashingchamber is passed back again into the dishwashing chamber after flowingthrough the condensation precipitation device.
 12. The dishwashingmachine according to claim 1, wherein the condensation precipitationdevice has at least one chamber with at least one inlet and at least oneoutlet and at least one condensation outflow.
 13. The dishwashingmachine according to claim 4, wherein the second fan is connected to theinlet and/or to the outlet.
 14. The dishwashing machine according toclaim 12, wherein the at least one chamber defines at least one flowchannel.
 15. The dishwashing machine according to claim 4, wherein thesecond fan is connected to the flow channel.
 16. The dishwashing machineaccording to claim 1, wherein the condensation precipitation device hasat least one condenser elements, the condenser elements including: atleast one cold plate; at least one cold plate that is sprayed with acooling medium; and/or at least one heat exchanger through which acooling medium flows, in particular a plate-type heat exchanger and/or aserpentine cooling coil-type heat exchanger.
 17. The dishwashing machineaccording to claim 16, wherein the at least one condenser element has atleast one of the following arrangements: the at least one condenserelement is aligned at an angle to the horizontal; the at least onecondenser element has a laminate arrangement; the at least one condenserelement has a meandering arrangement; or the at least one condenserelement has a parallel arrangement of at least two condenser elements.18. The dishwashing machine according to claim 1, wherein thecondensation precipitation device has at least one condenser elementthat is cooled with water, wherein the condenser element includes atleast one first condenser connection that is connected to a watersupply, in particular to a freshwater supply, and wherein thecondensation precipitation device includes at least one second condenserconnection connected to a tank for the dishwashing machine, inparticular to a final washing tank.
 19. The dishwashing machineaccording to claim 1, wherein the dishwashing machine performs adishwashing program, with the condensation precipitation device beingoperated in at least one program step in the dishwashing program inorder to suck vapor and/or air out of the dishwashing chamber.
 20. Thedishwashing machine according to claim 19, wherein at least one suctionprogram step is carried out at an end of the dishwashing program. 21.The dishwashing machine according to claim 1, wherein items to becleaned which are accommodated in the dishwashing chamber are finallywashed in at least one final washing program step using a final washingliquid from a final washing tank with cooling water being heated in asubsequent suction program step in the condensation precipitation deviceby vapor and/or air from the dishwashing chamber and with the heatedcooling water being passed into the final washing tank.
 22. Thedishwashing machine according to claim 21, wherein the final washingtank has a two-level control system, with the final washing program stepbeing carried out until a level in the final washing tank has reached alower level, and with the subsequent suction program step being carriedout until the level in the final washing tank has reached an upperlevel.
 23. The dishwashing machine according to claim 1, wherein atleast one liquid valve is provided for controlling a supply of a coolingmedium, with the dishwashing machine being designed in order tosynchronize the time of the operation of the liquid valve and theoperation of the fan.
 24. The dishwashing machine according to claim 23,wherein the dishwashing machine is designed such that the liquid valveis opened and a second fan is started substantially at the same time.